Description of the Related Art
Many conventional storage devices treat storage block addresses received from a storage client as logical block addresses having a one-to-one direct mapping to a corresponding physical addresses on a storage media where data is actually stored. For storage devices that maintain a mapping from a logical block address to an arbitrary physical address, conventional storage clients (operating systems, file systems, volume mangers, and the like) have begun to communicate when data on physical media corresponding to a logical block address no longer needs to be retained. This unused data block usage information enables deallocation of the corresponding physical blocks, and/or stops preserving the data in the corresponding physical blocks. As a result, data on the storage device corresponding to logical blocks that are not in use by a storage client, is no longer unnecessarily preserved by the storage device. Without this capability, unused data blocks must be preserved by the storage device as used data blocks, which slows performance and requires additional unnecessary overhead to maintain.
However, certain storage clients are not designed to communicate unused data block usage information. Additionally, certain storage clients that have the ability to communicate unused data block usage information do so ineffectively or lack the ability to communicate unused data block usage information for certain storage configurations. In addition, in certain storage configurations, even though the unused block usage information is communicated, the information is not passed on to the storage device.